Rotary pump



Sept; 9 1924. 1,507,611

F. A. LEIGH ROTARY PUMP Original Filed Feb. 1:5, 1922 2 Sheets-Sheet. 1

580%? L Giff Sept. 9,- 1924. 1,507,611

' F. A. LEIGH ROTARY PUMP Original Filed Feb. 13, 1922 2 Sheets-Sheet 2 Patented-Sept. 9, 1924.

UNITED STATES PATENT OFFICE.

FRED A. LEIGH, OF DETROIT, MICHIGAN.

mm rum.

Application filed February 13, 1922, Serial No. 536,112. Renewed February 11, 1924.

To all whom it may concern;

Be it known that I, FRED A. LEIGH, a citizen of the United States of America, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Rotary Pumps, of which the following is a specification, reference being had therein to the accompanying drawin s.

This invention re ates to rotary pumps, and more particularl to that type wherein a rotor is eccentrica ly disposed in a cylinder or chamber for inlet and outlet connections, and-the rotor rovided with pivoted pistons or liquid or uid shifting members which transfer the liquid or fluid from the inlet connection to the cylinder or chamber to the outlet connection thereof.

My invention aims to provide a rotary pump of the above ty e wherein a rotor has pistons or liquid or fluid shifting members of novel design, said pistons being automatic. in their action and highly eflicient-for moving a body of liquid or fluid; in connection with the pistons novel packing is employed to insure a positive contact between movable parts of the pump, so that leakage is reduced to a minimum and a maximum pumping suction of the pump at all times attained.

My invention further aims to provide a rotary pump structure wherein a cylinder has eccentrically disposed end flanges provided with concentric seats, said seats being eccentrically disposed relative to the axis of the cylinder and adapted to receive wear plates which are retained in position by eads connected to the flanges of the cylinder. This manner of assembling the wear plates and heads is advantageous from a manufacturing standpoint as there will be a minimum amount of machining.

My invention further aims to provide a rotary pump including a rotor having pivoted pistons which are movable in and out of the rotor and when within the rotor provide practically a solid rotor, there being no space or dead pockets to receive a liquid to be carried past the outlet and thereby reduce the efliciency of the pump. The packing associated with the pistons "prevents liquid from passing from the compression to the vacuum side of the pistons or blades and in this manner the pumping efliciency of the rotor is materially increased and a pump of maximum power obtained.

My inventlon further aims to provlde a simple, durable, inexpensive, and normally primed rotary pump which will be hereinafter specifically described and then claimed, reference being had to the drawings, wherem Figure 1 is a cross sectional view of the rotary pump;

Fig. 2 is a side elevation of the same, part- 1y broken away and partly in longitudinal section;

Fig. 3 is an end view of a detached rotor;

Fig. 4 is a side elevation of the same; I

Fig. 5 is an end view of a detached piston;

Fig. 6 is a side elevation of the same, and

Fig. 7 is a cross sectional view of the piston. a

In the drawings, the reference numeral 1 denotes a suitable base or foundation provided with a cylinder 2 having the upper portion thereof formed with an inlet connection 3 and an outlet connection 4,- these connections being tangentially disposed relative to the inner wall or chamber 5 of the cylinder.

The ends of the cylinder 2 are formed with peripheral flanges 6 having annular seats 7 for wear plates 8 which are set in said seats to close the ends of the chamber 5. The inner faces of these wear plates may be ground to present smooth and uninterrupted contact faces, and said wear plates are retained in the ends of the cylinder by heads 9 secured to the flanges 6 by screws 10 or other fastening means. The heads 9 are provided with lon ritudin'ally alining bearings 11 which are eccentrically disposed relative to the axis of the chamber 5, and journaled in the bearings 11 and extending through the wear plates 8 is a driven shaft12, said shaft edges from the body of t liquid receiving chamber between the rotor and the'lower portion of the cylinder 2 which space receives liquid from the inlet connection 3 to be transferred to the outlet connection 4.

The rotor 13 is provided with a plurality of curved pockets or slots 15 which extend longitudinally of the rotor and inwardly from its periphery with the ends of the pockets communicating with sector-shaped recesses 16 in the end walls of the rotor. In the recesses '16 are pivot pins or trunnions 17 and loose on said pivot pins or trunnions are the hook shaped ends 18 of side piston arms 19 integral with pistons or blades 20, said pistons being movable in and out of the pockets 15 as the arms 19 swing on the pins 17 in the recesses 16.,

with their ends contacting the wear plates 8 at the ends of the cylinder 2. The pistons or blades 20 are of segmental shape in cross section and each has a longitudinal slot or space 21 for a packing member or strip 22 made of any suitable material, such as leather or any other suitable substance that may contact with the inner wall of the chamber 5 and insure a reasonably *tight joint between the blades and the peripheral wall of the chamber.

The piston blades 20 are adapted to completely fill the pockets 15 when in retracted position and the packing 22 is made of a greater width than the width of the slots of said blades, so that the packing will protrude beyond the inner and outer edges of the blades, and slightly beyond the ends thereof. This is best shown in Figs. 5, 6 and 7, also in Fi 1, where it will be noted that the inner e ge of the packing is bent into contact with the rear wall of the pocket by the pressure of the fluid in said pocket, thus sealing the rear side of the pocket which is toward the vacuum or inlet side of the piston, so that fluid under compression in advance of the pistons can not escape past them to the vacuum or inlet side, causmg leakage and reducing the efliciency of the pump. Sim le, cheap and eflicient pis ton packing is t us provided, which packmg 1s such that it will not wear the wall of the slot and cause leakage and a tight ]omt is secured without the necessity for accurately machining either said wall or blade of the piston.

By making each piston blade with a face 2? to receive the ]packing strip 22 and prw vldmg a face p ate 26 which is secured against the strip b rivet-s 2" assin through the y p g plate strip and blade or otherwise connect said plate to the body of the piston, a simple construction is secured 1n which the packing -22 rotrudes at all a piston to engage the wall of the chamber 5, and seal the joint between the inner end of the blade and the rear wall of the slot in the rotor.

As shown in Fig. 3 the walls of the pockets 15 and a portion of the perlphe 14 of the rotor may be provided with dov tailed grooves 23 for anchoring linin 24 0f Babbitt metal or the like to face t ese pockets so that the rotor may be die cast with the slots or pockets therein without the necessity for machining the walls of the pockets, as the Babbitt meta-l or lining may be cast in the pockets to provide the necessary smooth surfaces to engage the piston blades.

When the shaft 12 is driven the pistons will be thrown outwardly by centrifugal force against the, walls of the chamber 5 and as' they-travel away from the inlet, a partial vacuum will be formed causing the fluid to flow in through the inlet, which liquid, being trapped between the pistons,

will be transferred from. the inlet connection 3 to the outlet connection 4, such transfer being continuous so that there may be an uninterrupted flow from the pump, espe cially when a head or column of liquid is maintained at the outlet connection 4. As the piston blades are designed to substantially fill the slots in the rotorand their arms to fill the end recesses the rotor,

when the pistons come to the upper side of the rotor during rotation and are forced toswing inwardly ment with the fluid is forced of the slots by their engagewall of the chamber 5, all out of these spaces in the rotor as they pass the outlet and substantially all of the fluid will be forced out of the outlet, making the pump very efficient as practically no fluid can be carried past the outlet.

The construction and arrangement of the cylinder casting, wear plates 8 and cylinder heads 9.is such that manufacture is greatly facilitated, in that the seats 7 for the plates are concentric with the axis of the bearings 11 for the shaft 12 which carries the rotor, and in securing the heads in place, the rotor may be adjusted in the cylinder accurately so that its periphery will just contact the wall of the cylinder, at the upper side thereof and be perfectly aligned therein.

My pump is highly eflicient for pum ing oil or other liquids and on account 0 the compact arrangement of the various parts, it may be constructed upon a small scale so as to adopt it for use in small s aces, such as the crank case of an automo ile engine to form part of the lubricant circulating system 0 such engine. The uses of the pump are-many and varied as it may be constructed in any size suitable to the work or installation and for this reason I do not care to confine my invention to the precme construction and arrangement of the parts by the aplade with said flexible edge portion engaging the rear wall of the pocket, to be held by fluid pressure against said wall and prevent leaka e rearwardly in the direction of rotation of:

the rotor, past said blades.

2. A rotary pump wherein a rotor is ec-. .centrically disposed within a cylinder having inlet and outlet connections, piston blades carried by said rotor, said rotor having pockets within which said blades are movable, said blades substantially filling said pockets when said blades are in retracted osition, means pivotally supporting said lades for movement into and out of said pockets of said rotor, said rotor being formed with recesses to receive said means with said means substantially filling said recesses when said blades are in retracted position, and packing carried by each blade, said pack- -mg comprising a flexible strip having an edge portion projecting beyond the inner side of the blade and adapted to be flexed laterally by fluid pressure into engagement with the rear wall of the pocket for the piston to seal the joint between said piston and said wall and prevent leakage past the pistons rearwardly in the direction of r0 tation during the movement of said pistons.

3. A rotary pum as in claim 2 characterized in that the exible strip is of fibrous material and formed with a thinned edge,-

the stri plate, t e plate and strip bein relatively positioned in such wa that the t inned edge projects beyond the mner edge of the face plate at the inner side of the piston to form being secured position by a face 1 the portion of the strip to be flexed into engagement with the rear wall of the pocket.

4. In rotary pump formations wherein the stator member and rotor are of eccentric relation, and wherein the rotor carries a plurality of pivoted'elements movable relativeto plockets during the travel of the blade of eac element in contact with the circular face of the stator member, the space between successive blades forming a chamber for receiving the fluid from the intake and delivering it to the outlet of the stator member, means carried by each element for preventing leakage from an advance to a rear chamber during the period of travel from the intake to the outlet, said means including a flexible formation carried by the element and having its end faces in contact with the wear plates of the stator and its outer face maintained in contact with the circular wall of the stator member by the travel of the rotor, said formation having a portion projecting from the face of the element opposite such outer contacting face of the formation, said projecting portion having a cross-sectional configuration such as to provide for flexibility thereof and prositioned to per element therein and in presence of fluid pressure within the advance chamber.

In'testimony whereof I aflix my signature in presence of two witnesses. v

. FRED A. LEIG Witnesses:

ANNA M. Dona, 

